Spectral structure and subdecomposability of 𝑝-hyponormal operators

Yingbin, Ruan; Zikun, Yan

doi:10.1090/S0002-9939-99-05257-0

Spectral structure and subdecomposability of $p$-hyponormal operators
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by Ruan Yingbin and Yan Zikun

Proc. Amer. Math. Soc. 128 (2000), 2069-2074

DOI: https://doi.org/10.1090/S0002-9939-99-05257-0

Published electronically: October 29, 1999

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Abstract:

We prove that for every $p$-hyponormal operator $A, 0<p\le 1,$ there corresponds a hyponormal operator $\tilde A$ such that $A$ and $\tilde A$ have “equal spectral structure". We also prove that every $p$-hyponormal operator $A,0<p\le 1,$ is subdecomposable. Then some relevant quasisimilarity results are obtained, including that two quasisimilar $p$-hyponormal operators have equal essential spectra.

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